1. Field of the Invention
This invention pertains to a book binding method and binder for retaining and clamping a margin of apertured material such as a stack of hole punched sheets. More particularly, the invention is directed to binding elements to bind a sheaf of papers into a bound report or booklet without the use of any machinery or hand tool. An improved spine cover may also be utilized with the binder elements.
2. Material Information
Various binding systems have been utilized in the past such as the common ring binder, the Acco fastener type, the plastic spiral binder, interlocking through-hole devices, and the plastic headed stud and strips type. The latter two types of binders are exemplified by U.S. Pat. No. 3,970,331 where ratchet teeth are employed on a stud which engage a mating ratchet tooth with a blocking means for permanently holding the matching teeth together; U.S. Pat. No. 4,175,880 where alternate detent containing sleeves extend from binding strips into a stack of writing material; U.S. Pat. No. 4,369,013 where studs integral with a strip are sheared and headed by a machine to clamp a sheaf of papers between two strips; and U.S. Pat. No. 1,841,989 which shows a wedge lock binder for apertured sheets. U.K. Patent No. 950,768 shows a pair of ratcheted rods on a strip with toothed washers forced downwardly on the rods to firmly grasp a stack of sheets. Hinged pawls have been employed in the so-called cable tie art where a one-piece flexible strap with ratchet teeth is utilized to clamp a bundle of wires. U.S. Pat. No. 4,287,644, exemplifies this art.
The prior art in most instances requires the use of special binding machinery or hand tools and in most cases, requires destruction of the binding elements if it is desired to replace a sheet within the bound stack. Further, several of the prior art devices have serrations which tend to tear the edges of the through-holes in the paper stack through which the binding elements pass and are not adaptable to incorporation of spine covers or overall booklet covers.